The present technology relates to imaging devices and, in particular, to imaging devices to be designed with a high degree of freedom at low cost without impairing accuracy of focus detection, image quality, and the like.
In the past, imaging devices have been proposed that include pixels outputting imaging signals (hereinafter referred to as normal pixels) and pixels detecting a focal length (hereinafter referred to as AF (auto focus) pixels) both formed on one chip (see, for example, Japanese Unexamined Patent Application Publication No. 2000-292686).
According to the technique disclosed in Japanese Unexamined Patent Application Publication No. 2000-292686, pupil-division microlenses and pairs of light-receiving elements that receive pupil division light etc. are formed in a plurality of regions on the chip of the imaging device, and focus detection is performed based on the output of the light-receiving elements. This makes it possible to provide a wider focus detection region while saving space without adding, for example, a new mechanism or an optical system, increase an AF speed, and perform accurate focusing.
Moreover, to increase the accuracy of focus detection, it is necessary for AF pixels to be irradiated with incident light from a constant direction. It is for this reason that adopting a configuration in which a light-blocking film is provided over part of the AF pixel, for example, has been proposed (for example, Japanese Unexamined Patent Application Publication No. 2009-105358).
According to the technique of Japanese Unexamined Patent Application Publication No. 2009-105358, a light-blocking film with an opening is disposed over an AF pixel from which light enters, and the opening defines a region through which the incident light enters a photoelectric conversion section. As a result, the photoelectric conversion section of the AF pixel selectively receives the luminous flux coming through a region in an exit pupil of a taking lens, the region that is substantially eccentric from the center of the exit pupil in -Y direction, and performs photoelectric conversion.